FIGS. 4 and 5 show a conventional apparatus for supplying resin tablets for use in sealing a semiconductor device. As best seen from FIG. 4, the supplying apparatus operates as in the following. An arm 1 moves upward to supply a tablet 2 one at a time to a tablet chuck 3. When all tablets in a tablet stocker 4a are discharged, a stocker table 5 is rotated about a shaft 16 to move another tablet stocker 4b to the position where the table stocker 4a was located as shown in FIG. 4. By repeating the above operations, the tablets in the stockers 4a and 4b are supplied to the chuck 3.
The arm 1 is moved upward/downward as an arm up/down drive motor 8 rotates. The rotation of the motor 8 is transmitted via a rotation transmission mechanism 9 to an arm up/down drive shaft 10 made of a screw.
The shaft 10 has a female screw member 11, both being rotatable relative to each other. When the shaft 10 rotates in the normal/reverse direction, the female screw member 11 moves upward/downward. The arm 1 is fixedly mounted on the female screw member 11 so that the arm 1 is moved upward/downward together with the female screw member 11.
The stocker table 5 is rotated by a stocker table drive motor 13. The rotation of the motor 13 is transmitted via a rotation transmission mechanism 14 to a stocker table drive mechanism 15. The drive mechanism 15 transforms the transmitted rotation into the rotation of a shaft 16. The stocker table 5 rotates together with the shaft 16.
With the above operations when a tablet 2 is supplied to the tablet chuck 3, the tablet chuck 3 holds and sends it to a preheat process or directly to a molding process.
The above-described apparatus has the following problems:
(a) If the size, i.e., axial length (thickness, width), of the tablet 2 is changed, it is necessary to adjust or exchange the chuck 3 and stocker table 5 so as to meet the changed size. During such adjustment or exchange work, a supply of tablets 2 is stopped to thereby lower the operation rate of the apparatus. It is necessary to lower the arm 1 positioned at an upper position to the lower limit position and to rotate the stocker table 5 when the tablet stocker 4a is exchanged for the tablet stocker 4b. Therefore the operation rate of the apparatus becomes lower.
(b) In order to continuously supply tablets 2, it is necessary to prepare space for installing one or a plural number of tablet stockers 4a, 4b. It is also necessary to provide a mechanism and space for rotating the stocker table 5 in a horizontal plane to change from the tablet stocker 4a to the stocker 4b. The apparatus therefore becomes large, complex and expensive.
(c) Since the tablet 2 is supplied to the chuck 3 at a fixed position, the usage efficiency of apparatus space is poor.